Method for regenerating insulating oil

Abstract

To provide a method for efficiently performing maintenance and inspection (including repair) of a plurality of oil-filled electric apparatuses and regeneration treatment of insulating oil.SOLUTION: The method comprises a first step of transferring the insulating oil of the oil-filled electric apparatus and storing it in the 31A, 31B, and 31C of the oil reservoir tank, a second step of maintaining and inspecting the oil-filled electric apparatus with the insulating oil transferred, and a third step of transferring the insulating oil in the 31A, 31B, and 31C of the oil reservoir tank, regenerating it, and returning it to the oil-filled electric apparatus. The first step, the second step, and the third step are performed in parallel in order from the first oil-filled electrical device so that the same step does not overlap among the plurality of oil-filled electrical devices.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for efficiently carrying out maintenance and inspection (including repair) of a plurality of oil-filled electrical devices and for efficiently regenerating insulating oil. [Background technology]

[0002] Conventionally, maintenance and inspection of oil-filled electrical equipment has been carried out after the insulating oil has been removed from the electrical equipment. The removed insulating oil is purified and then returned to the electrical equipment after the maintenance and inspection has been completed (see Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2002-15922 Summary of the Invention [Problem to be solved by the invention]

[0004] The method described in Patent Document 1 is based on the premise that maintenance and inspection of one oil-filled electrical device and purification of the insulating oil are performed. Therefore, when performing maintenance and inspection of multiple oil-filled electrical devices and purification of the insulating oil, it is necessary to complete the maintenance and inspection of the first oil-filled electrical device and purification of the insulating oil before starting the maintenance and inspection of the second oil-filled electrical device and purification of the insulating oil.

[0005] As a result, it took a long time to complete the maintenance and inspection of multiple oil-filled electrical devices and the purification of insulating oil, which was inefficient.

[0006] Furthermore, the insulating oil treatment device described in Patent Document 1 requires connecting a pressure relief pipe to the transformer tank and connecting piping to valve 9, so after completing the maintenance and inspection of the first oil-filled electrical device and the insulating oil purification treatment, it is necessary to remove the pressure relief pipe and connecting piping and reconnect them to the second oil-filled electrical device, which is likely to result in a significant workload.

[0007] The present invention solves these problems and provides a method for efficiently performing maintenance and inspection (including repair) of multiple oil-filled electrical devices and recycling of insulating oil. [Means for solving the problem]

[0008] The invention described in claim 1 is an insulating oil regeneration method in which a plurality of oil-filled electrical equipment perform the following steps in parallel in the stated order: a first step of transferring insulating oil from oil-filled electrical equipment and storing it in an oil tank; a second step of maintaining and inspecting the oil-filled electrical equipment to which the insulating oil has been transferred; and a third step of transferring the insulating oil in the oil tank, regenerating it, and then returning the insulating oil to the oil-filled electrical equipment, wherein the second oil-filled electrical equipment performs the first and second steps while the previous oil-filled electrical equipment is performing the third step.

[0009] The invention described in claim 2 is a method for recycling insulating oil described in claim 1, characterized in that the process of recycling insulating oil makes it possible to select between a process of recycling insulating oil and a process of disposing of it.

[0010] The invention described in claim 3 is a method for regenerating insulating oil described in claim 2, characterized in that the process of regenerating the insulating oil comprises at least one of a process of degassing the insulating oil and a process of filtering the insulating oil. [Effects of the Invention]

[0011] According to the invention of claim 1, maintenance and inspection (including repair) of a plurality of oil-filled electrical devices and regeneration of insulating oil can be carried out efficiently in a short time.

[0012] According to the invention of claim 2, it is possible to select between recycling and discarding the insulating oil depending on the deterioration state of the insulating oil.

[0013] According to the invention of claim 3, a regeneration method can be selected depending on the deterioration state of the insulating oil. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a configuration diagram showing an embodiment of an insulating oil regeneration treatment device according to the present invention. [Figure 2] FIG. 2 is a configuration diagram showing another embodiment of an insulating oil recycling treatment device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] An embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a configuration diagram showing an insulating oil regeneration treatment device A according to the present invention. In Fig. 1, 1A, 1B, and 1C are tanks for oil-filled electrical equipment such as transformers, and 2A, 2B, and 2C are electrical equipment bodies installed in the tanks 1A, 1B, and 1C. The electrical equipment bodies 2A, 2B, and 2C are respectively composed of coils 2A1, 2B1, and 2C1 and iron cores 2A2, 2B2, and 2C2, and are immersed in insulating oil 3A, 3B, and 3C filled in the tanks 1A, 1B, and 1C.

[0016] Reference numeral 4a denotes a filtering device connected to the inside of tanks 1A, 1B, and 1C by oil supply pipes 5e to 5g, and reference numerals 6a and 6b denote filters containing different adsorbents, which may be known adsorbents (such as clay or activated alumina).

[0017] Reference numeral 7 denotes a heater that heats the insulating oil flowing through pipe 9 in filtration device 4a to a predetermined temperature (for example, 40°C), and 8 denotes a pressure gauge that measures the dynamic pressure of the insulating oil flowing through pipe 9. Reference numeral 10 denotes a pump that causes the insulating oil to flow through pipe 9, and 11a denotes a valve installed on pipe 9 between filters 6a, 6b and heater 7.

[0018] Reference numeral 12 denotes a measuring instrument consisting of a conductivity meter or a dielectric constant meter, etc., installed on the oil supply pipe 5c which is connected to the oil supply pipes 5e to 5g, 13c denotes a valve installed on the oil supply pipe 5e, 13d denotes a valve installed on the oil supply pipe 5f, and 13e denotes a valve installed on the oil supply pipe 5g.

[0019] 31A is an oil storage tank that temporarily stores the insulating oil 3A in tank 1A after it has been transferred, 31B is an oil storage tank that temporarily stores the insulating oil 3B in tank 1B after it has been transferred, and 31C is an oil storage tank that temporarily stores the insulating oil 3C in tank 1C after it has been transferred.

[0020] Reference numeral 14a denotes an oil feed pipe for feeding insulating oil 3A, 3B, and 3C in tanks 1A, 1B, and 1C, and reference numeral 32a denotes an oil feed pipe for feeding insulating oil 3A into oil reservoir tank 31A via valve 34a using pump 33a. Reference numeral 32b denotes an oil feed pipe for feeding insulating oil 3B into oil reservoir tank 31B via valve 34b using pump 33b, and reference numeral 32c denotes an oil feed pipe for feeding insulating oil 3C into oil reservoir tank 31C via valve 34b using pump 33c.

[0021] Reference numeral 15 denotes a new oil tank that stores unused insulating oil (new oil) 3D. Reference numeral 16 denotes an oil supply pipe for supplying the new oil 3D in the new oil tank 15, and reference numeral 17 denotes a valve installed on the oil supply pipe 16.

[0022] Reference numeral 35a denotes an oil feed pipe for feeding insulating oil 3A temporarily stored in oil reservoir tank 31A, 35b denotes an oil feed pipe for feeding insulating oil 3B temporarily stored in oil reservoir tank 31B, 35c denotes an oil feed pipe for feeding insulating oil 3C temporarily stored in oil reservoir tank 31C, and 35d denotes an oil feed pipe that communicates with oil feed pipes 35a, 35b, and 35c via valves 36a and 36b.

[0023] Reference numeral 18 denotes a valve for allowing insulating oil 3A, 3B, 3C flowing through oil feed pipe 35d or new oil 3D flowing through oil supply pipe 16 to flow into oil feed pipe 14b, and 19 denotes an oil treatment tank for storing insulating oil 3E that has been degassed. Reference numeral 20 denotes a nozzle attached to the tip of oil feed pipe 14b that is inserted into oil treatment tank 19 from the top, and 21 denotes a vacuum pump for reducing the pressure inside oil treatment tank 19.

[0024] Reference numeral 22 denotes a valve that is opened when the vacuum pump 21 reduces the pressure inside the oil treatment tank 19, and 23 denotes a pressure gauge for measuring the pressure inside the oil treatment tank 19. The pressure gauge 23 is used to manage the pressure inside the oil treatment tank 19 that is being reduced in pressure by the vacuum pump 21.

[0025] Reference numeral 24 denotes an oil inflow prevention unit installed in oil treatment tank 19, which prevents insulating oil 3E from flowing into vacuum pump 21 when the pressure inside oil treatment tank 19 is reduced by vacuum pump 21. The oil inflow prevention unit 24 may have a structure such as a bottomed semi-cylindrical shape with an opening at the top, and is installed by fixing the cylindrical part and the open side of the bottom to the inner peripheral surface of oil treatment tank 19 by welding or the like. Reference numeral 25 denotes a valve for returning the pressure inside oil treatment tank 19 to atmospheric pressure.

[0026] Reference numeral 26 denotes a discharge pipe connected to the lower drain of the oil treatment tank 19, and 27 denotes a valve installed on the discharge pipe 26. Reference numeral 28 denotes a waste oil pipe that communicates with the discharge pipe 26 by switching the valve 29, and by switching the valve 29, the insulating oil 3E flowing through the discharge pipe 26 can be made to flow into the oil feed pipe 5d or into the waste oil pipe 28. Reference numeral 30 denotes a waste oil tank that stores the insulating oil 3E1 discharged through the waste oil pipe 28.

[0027] Next, we will explain the operation of the regeneration treatment device A. When regenerating insulating oil and performing maintenance and inspection (including repair) on multiple oil-filled electrical devices, first, oil supply pipe 14a is inserted into tank 1A of the first oil-filled electrical device, and valve 34a is switched to connect the inside of tank 1A to the inside of oil storage tank 31A through oil supply pipe 14a.

[0028] In this state, the vacuum pump 33a is driven to transfer the insulating oil 3A in the tank 1A to the oil reservoir tank 31A through the oil feed pipe 14a. Next, the oil feed pipe 14a is moved into the tank 1B of the second oil-filled electrical device, and maintenance and inspection of the first oil-filled electrical device is carried out. If any abnormalities such as breakdowns are discovered during the maintenance and inspection, repairs are carried out.

[0029] When the maintenance and inspection (including repairs) of the first oil-filled electrical device is completed, valve 34b is switched to connect the inside of tank 1B of the second oil-filled electrical device to the inside of oil reservoir tank 31B via oil feed pipe 14a.

[0030] In this state, vacuum pump 33b is driven to transfer insulating oil 3B from tank 1B to oil reservoir tank 31B through oil feed pipe 14a. Next, oil feed pipe 14a is moved into tank 1C of the third oil-filled electrical device, and maintenance and inspection of the second oil-filled electrical device is carried out. If any abnormalities such as malfunctions are discovered during the maintenance and inspection, repairs are carried out.

[0031] At the same time, valves 18 and 36a are switched to connect the oil reservoir tank 31A to the oil treatment tank 19, and pump 21 is driven to suck up insulating oil 3A from the oil reservoir tank 31A. The sucked-up insulating oil 3A is sprayed from nozzle 20 into the oil treatment tank 19 in the form of a shower or mist. Moisture and decomposition gases are removed from the insulating oil 3A sprayed out in the form of a shower or mist, and the oil is stored in the oil treatment tank 19.

[0032] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0033] When the pressure is reduced, the insulating oil 3E in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0034] After the above degassing process, the insulating oil 3E is passed through the discharge pipe 26 and the oil supply pipe 5d by the valve 29 while the valves 25 and 27 are open and one of the valves 13c to 13e is also open, and the pump 10 of the filtration device 4a is driven to flow the insulating oil 3E from the discharge pipe 26 through the oil supply pipe 5d into the pipe 9 of the filtration device 4a.

[0035] In the filtration device 4a, the dynamic pressure of the insulating oil 3E flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3E is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3E flows to the oil supply pipe 5g, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0036] When the insulating oil 3E flows into the oil supply pipe 5g, the degree of deterioration of the insulating oil 3E is measured by the measuring instrument 12 on the oil supply pipe 5c, and then the insulating oil 3A in the tank 1A is supplied to the tank 1A. In this case, the insulating oil 3A in the tank 1A is degassed in the oil treatment tank 19 and returned to the tank 1A.

[0037] When the oil flows to the filter 6b, solids such as carbon and sludge are removed by an adsorbent (for example, clay) in the filter 6b. The insulating oil 3E that has passed through the filter 6b is measured for its degree of deterioration by a measuring instrument 12 on the oil supply pipe 5c, and then is poured into the tank 1A. In this case, the insulating oil 3A in the tank 1A is returned to the tank 1A after being degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a.

[0038] When the oil flows into the filter 6a, solids such as carbon and sludge are removed by an adsorbent (for example, activated alumina) in the filter 6a. The insulating oil 3E that has passed through the filter 6a has its degree of deterioration measured by a measuring instrument 12 on the oil supply pipe 5c, and is then fed into the tank 1A. In this case, the insulating oil 3A in the tank 1A is degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a before being returned to the tank 1A.

[0039] When the insulating oil 3E is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3E to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3E is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3E with the heater 7.

[0040] In this way, the degree of deterioration of the insulating oil 3A in the tank 1A is improved by passing it through the oil treatment tank 19 and the filtration device 4a, and it can be returned to the tank 1A as recycled oil. By repeating this recycling process, the measurement value by the measuring instrument 12 on the oil supply pipe 5c improves.

[0041] The filters 6a and 6b that make up the filtration device 4a become clogged with the adhesion of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3E measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading of the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filter 6.

[0042] Once the maintenance and inspection (including repairs) of the second oil-filled electrical device and the regeneration of the insulating oil of the first oil-filled electrical device are completed, valve 34b is switched to connect the inside of tank 1C of the third oil-filled electrical device to the inside of oil reservoir tank 31C via oil supply piping 14a.

[0043] In this state, the vacuum pump 33c is driven to transfer the insulating oil 3C in the tank 1C to the oil reservoir tank 31C through the oil transfer pipes 14a and 32c. Once all the insulating oil 3C in the tank 1C has been transferred, maintenance and inspection of the third oil-filled electrical device is carried out. If any abnormalities such as breakdowns are discovered during the maintenance and inspection, repairs are carried out.

[0044] At the same time, valves 18 and 36b are switched to operate pump 21 while oil reservoir tank 31B is in communication with oil treatment tank 19, and insulating oil 3B is sucked up from oil reservoir tank 31B. The sucked-up insulating oil 3B is sprayed in a shower or mist form from nozzle 20 into oil treatment tank 19. Moisture and decomposition gases are removed from insulating oil 3B sprayed in a shower or mist form, and the oil is stored in oil treatment tank 19.

[0045] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0046] When the pressure is reduced, the insulating oil 3E in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0047] After the above degassing process, the insulating oil 3E is passed through the discharge pipe 26 and the oil supply pipe 5d by the valve 29 while the valves 25 and 27 are open and one of the valves 13c to 13e is also open, and the pump 10 of the filtration device 4a is driven to flow the insulating oil 3E from the discharge pipe 26 through the oil supply pipe 5d into the pipe 9 of the filtration device 4a.

[0048] In the filtration device 4a, the dynamic pressure of the insulating oil 3E flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3E is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3E flows to the oil supply pipe 5g, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0049] When the insulating oil 3E flows into the oil supply pipe 5g, the degree of deterioration of the insulating oil 3E is measured by the measuring instrument 12 on the oil supply pipe 5c, and then the insulating oil 3B in the tank 1B is supplied to the tank 1B. In this case, the insulating oil 3B in the tank 1B is degassed in the oil treatment tank 19 and returned to the tank 1B.

[0050] When the oil flows to filter 6b, solids such as carbon and sludge are removed by an adsorbent (e.g., clay) in filter 6b. After passing through filter 6b, the insulating oil 3E is fed into tank 1B after its degree of deterioration is measured by measuring instrument 12 on oil feed pipe 5c. In this case, insulating oil 3B in tank 1B is returned to tank 1B after being degassed in oil treatment tank 19 and regenerated by filtration in filter device 4a.

[0051] When the oil flows into the filter 6a, solids such as carbon and sludge are removed by an adsorbent (e.g., activated alumina) in the filter 6a. The insulating oil 3E that has passed through the filter 6a is measured for its degree of deterioration by a measuring instrument 12 on the oil supply pipe 5c, and then fed into the tank 1B. In this case, the insulating oil 3B in the tank 1B is degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a before being returned to the tank 1B.

[0052] When the insulating oil 3E is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3E to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3E is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3E with the heater 7.

[0053] In this way, the degree of deterioration of the insulating oil 3B in the tank 1B is improved by passing it through the oil treatment tank 19 and the filtration device 4a, and it can be returned to the tank 1B as recycled oil. By repeating this recycling process, the measurement value by the measuring instrument 12 on the oil supply pipe 5c improves.

[0054] The filters 6a and 6b that make up the filtration device 4a become clogged with the adhesion of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3E measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading of the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filter 6.

[0055] Once the maintenance and inspection (including repairs) of the third oil-filled electrical equipment and the regeneration of the insulating oil of the second oil-filled electrical equipment are completed, valves 18 and 36b are switched to connect the oil reservoir tank 31C to the oil treatment tank 19, and pump 21 is driven to suck up the insulating oil 3C from the oil reservoir tank 31C. The sucked-up insulating oil 3C is sprayed from nozzle 20 into the oil treatment tank 19 in the form of a shower or mist. Moisture and decomposition gases are removed from the insulating oil 3C sprayed out in the form of a shower or mist, and the oil is stored in the oil treatment tank 19.

[0056] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0057] When the pressure is reduced, the insulating oil 3E in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0058] After the above degassing process, the insulating oil 3E is passed through the discharge pipe 26 and the oil supply pipe 5d by the valve 29 while the valves 25 and 27 are open and one of the valves 13c to 13e is also open, and the pump 10 of the filtration device 4a is driven to flow the insulating oil 3E from the discharge pipe 26 through the oil supply pipe 5d into the pipe 9 of the filtration device 4a.

[0059] In the filtration device 4a, the dynamic pressure of the insulating oil 3E flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3E is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3E flows to the oil supply pipe 5g, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0060] When the insulating oil 3E flows into the oil supply pipe 5g, the degree of deterioration of the insulating oil 3E is measured by the measuring instrument 12 on the oil supply pipe 5c, and then the insulating oil 3E is supplied into the tank 1C. In this case, the insulating oil 3C in the tank 1C is degassed in the oil treatment tank 19 and returned to the tank 1C.

[0061] When the oil flows to the filter 6b, solids such as carbon and sludge are removed by an adsorbent (for example, clay) in the filter 6b. The insulating oil 3E that has passed through the filter 6b is measured for its degree of deterioration by a measuring instrument 12 on the oil supply pipe 5c, and then is poured into the tank 1C. In this case, the insulating oil 3C in the tank 1C is returned to the tank 1C after being degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a.

[0062] When the oil flows into the filter 6a, solids such as carbon and sludge are removed by an adsorbent (for example, activated alumina) in the filter 6a. The insulating oil 3E that has passed through the filter 6a is fed into the tank 1C after the degree of deterioration is measured by a measuring instrument 12 on the oil feeding pipe 5c. In this case, the insulating oil 3C in the tank 1C is degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a before being returned to the tank 1C.

[0063] When the insulating oil 3E is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3E to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3E is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3E with the heater 7.

[0064] In this way, the degree of deterioration of the insulating oil 3C in the tank 1C is improved by passing it through the oil treatment tank 19 and the filtration device 4a, and it can be returned to the tank 1C as recycled oil. By repeating this recycling process, the measurement value by the measuring instrument 12 on the oil supply pipe 5c improves.

[0065] The filters 6a and 6b that make up the filtration device 4a become clogged with the adhesion of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3E measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading of the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filter 6.

[0066] 1 can also mix new oil 3D and return it to tanks 1A-1C during the process of regenerating insulating oil 3A-3C in tanks 1A-1C. In this case, valve 17 on oil supply pipe 16 is opened around the time of oil transfer from oil reservoir tanks 31A-31C to oil treatment tank 19, and vacuum pump 21 transfers new oil 3D from oil supply pipe 16 through oil transfer pipe 14b and nozzle 20 into oil treatment tank 19. In oil treatment tank 19, insulating oil 3A-3C transferred from tank 1 and new oil 3D in new oil tank 15 are mixed together.

[0067] The process of returning the mixed insulating oil 3E to the tanks 1A to 1C through the filtration device 4a is the same as that described above, so a detailed explanation will be omitted. The insulating oil 3E, which is a mixture of the insulating oils 3A to 3C and the new oil 3D, has a dramatically improved degree of deterioration, and the measurement value measured by the measuring instrument 12 also improves.

[0068] If the insulating oil 3A-3C in the tanks 1A-1C has deteriorated so much that it cannot be regenerated by the regeneration process described above, the insulating oil 3A-3C in the tanks 1A-1C can be discarded and only new oil 3D can be poured into the tanks 1A-1C. When pouring only new oil 3D into the tanks 1A-1C, first, the valve 18 is switched to connect the oil reservoir tanks 31A-31C to the oil treatment tank 19.

[0069] In this state, by opening valve 22 and driving vacuum pump 21, insulating oil 3A to 3C is sucked up from one of oil reservoir tanks 31A, 31B, 31C through oil supply pipe 35d, and the insulating oil 3A to 3C is transferred from nozzle 20 into oil treatment tank 19.

[0070] The insulating oil 3E accumulated in the oil treatment tank 19 is discharged from the discharge pipe 26 through the waste oil pipe 28 to the waste oil tank 30 by opening the valves 25 and 27 and switching the valve 29 to connect the discharge pipe 26 and the waste oil pipe 28.

[0071] Next, valves 25 and 27 are closed, valve 17 is opened, and valve 18 is switched to connect oil supply pipe 16 and oil transfer pipe 14b, and pump 21 is driven to transfer new oil 3D from new oil tank 15 into oil treatment tank 19. Once new oil 3D has accumulated in oil treatment tank 19, valve 18 is switched to eliminate the connection between oil supply pipe 16 and oil transfer pipe 14b, and valve 29 is switched to connect discharge pipe 26 and oil transfer pipe 5d.

[0072] Next, valve 27 is opened, and with one of valves 13c to 13e open, pump 10 of filtration device 4a is driven, thereby injecting new oil 3D from oil treatment tank 19 into one of tanks 1A to 1C through discharge pipe 26, oil supply pipe 5d, pipe 9 of filtration device 4a, and oil injection pipes 5e to 5g and 5c.

[0073] The new oil 3D may be heated by the heater 7 and then returned to one of the tanks 1A to 1C via the filter 6a (6b), or it may be returned to one of the tanks 1A to 1C via the oil supply pipe 5g without being heated by the heater 7.

[0074] The operation of the regeneration treatment device A can be performed automatically or semi-automatically. For example, if the measurement by the measuring device 12 shows that the insulating oil is not very deteriorated, the various valves and pumps are controlled so that filtration by the filter 6a (6b) is not performed and only degassing treatment is performed in the oil treatment tank 19.

[0075] If the insulating oil is severely deteriorated, the various valves and pumps are controlled to perform both the selection and filtration by the filter 6a (6b) and the degassing treatment in the oil treatment tank 19. Alternatively, the deterioration state of the insulating oil 3A to 3C in the tanks 1A to 1C may be resolved by controlling the various valves and pumps to mix the insulating oil 3A to 3C in the tanks 1A to 1C with the insulating oil 3D in the new oil tank 15 and return the mixture to the tanks 1A to 1C.

[0076] If the insulating oil is severely deteriorated and cannot be regenerated, the various valves and pumps are controlled to discharge the insulating oil 3A to 3C into the waste oil tank 30 and to pour only new oil 3D into the tanks 1A to 1C. Naturally, all or part of the control of the various valves and pumps may be manually operated.

[0077] 1 illustrates a case where oil inflow prevention unit 24 is attached to oil treatment tank 19, but the vacuum pump 21 and valve 22 may be attached at the positions shown by dotted lines in Fig. 1, and insulating oil 3E may be prevented from flowing into vacuum pump 21 by drawing a vacuum from the top of oil treatment tank 19. With this configuration, oil inflow prevention unit 24 is not necessary.

[0078] Furthermore, the regeneration treatment device A is configured to select and filter the filters 6a and 6b containing the optimal adsorbent according to the measurement value obtained by the measuring device 12. While Fig. 1 illustrates a case in which two filters 6a and 6b are provided, the number of filters constituting the present invention is not limited to two, and the device may be configured with more than two filters. By installing additional valves downstream of the valve 11a according to the number of filters, a large number of filters can be selected.

[0079] Figure 2 is a configuration diagram showing an insulating oil recycling treatment device B according to the present invention. In Figure 2, 1A, 1B, and 1C are tanks for oil-filled electrical equipment such as transformers, and 2A, 2B, and 2C are electrical equipment bodies installed in the tanks 1A, 1B, and 1C. The electrical equipment bodies 2A, 2B, and 2C are respectively composed of coils 2A1, 2B1, and 2C1 and iron cores 2A2, 2B2, and 2C2, and are immersed in insulating oil 3A, 3B, and 3C filled in the tanks 1A, 1B, and 1C.

[0080] Reference numeral 4a denotes a filtering device connected to oil supply pipes 5h, 5i, and 5j, each equipped with valves 13c, 13d, and 13e, and reference numerals 6a and 6b denote filters each containing a different adsorbent, which may be a known adsorbent (such as clay or activated alumina).

[0081] Reference numeral 7 denotes a heater that heats the insulating oil flowing through pipe 9 in filtration device 4a to a predetermined temperature (for example, 40°C), and 8 denotes a pressure gauge that measures the dynamic pressure of the insulating oil flowing through pipe 9. Reference numeral 10 denotes a pump that causes the insulating oil to flow through pipe 9, and 11a denotes a valve installed on pipe 9 between filters 6a, 6b and heater 7.

[0082] 31A is an oil storage tank that temporarily stores the insulating oil 3A in tank 1A after it has been transferred, 31B is an oil storage tank that temporarily stores the insulating oil 3B in tank 1B after it has been transferred, and 31C is an oil storage tank that temporarily stores the insulating oil 3C in tank 1C after it has been transferred.

[0083] Reference numeral 14a denotes an oil feed pipe for feeding insulating oil 3A, 3B, and 3C in tanks 1A, 1B, and 1C, and reference numeral 32a denotes an oil feed pipe for feeding insulating oil 3A into oil reservoir tank 31A via valve 34a using pump 33a. Reference numeral 32b denotes an oil feed pipe for feeding insulating oil 3B into oil reservoir tank 31B via valve 34b using pump 33b, and reference numeral 32c denotes an oil feed pipe for feeding insulating oil 3C into oil reservoir tank 31C via valve 34b using pump 33c.

[0084] Reference numeral 15 denotes a new oil tank that stores unused insulating oil (new oil) 3D. Reference numeral 16 denotes an oil supply pipe for supplying the new oil 3D in the new oil tank 15, and reference numeral 17 denotes a valve installed on the oil supply pipe 16.

[0085] Reference numeral 35a denotes an oil feed pipe for feeding insulating oil 3A temporarily stored in oil reservoir tank 31A, 35b denotes an oil feed pipe for feeding insulating oil 3B temporarily stored in oil reservoir tank 31B, 35c denotes an oil feed pipe for feeding insulating oil 3C temporarily stored in oil reservoir tank 31C, and 35d denotes an oil feed pipe that communicates with oil feed pipes 35a, 35b, and 35c via valves 36a and 36b.

[0086] Reference numeral 18 denotes a valve for allowing insulating oil 3A, 3B, 3C flowing through oil feed pipe 35e or new oil 3D flowing through oil supply pipe 16 to flow into oil feed pipe 14b, and 19 denotes an oil treatment tank for storing insulating oil 3E that has been degassed. Reference numeral 20 denotes a nozzle attached to the tip of oil feed pipe 14b that is inserted into oil treatment tank 19 from the top, and 21 denotes a vacuum pump for reducing the pressure inside oil treatment tank 19.

[0087] Reference numeral 22 denotes a valve that is opened when the vacuum pump 21 reduces the pressure inside the oil treatment tank 19, and 23 denotes a pressure gauge for measuring the pressure inside the oil treatment tank 19. The pressure gauge 23 is used to manage the pressure inside the oil treatment tank 19 that is being reduced in pressure by the vacuum pump 21.

[0088] Reference numeral 24 denotes an oil inflow prevention unit installed in oil treatment tank 19, which prevents insulating oil 3E from flowing into vacuum pump 21 when the pressure inside oil treatment tank 19 is reduced by vacuum pump 21. The oil inflow prevention unit 24 may have a structure such as a bottomed semi-cylindrical shape with an opening at the top, and is installed by fixing the cylindrical part and the open side of the bottom to the inner peripheral surface of oil treatment tank 19 by welding or the like. Reference numeral 25 denotes a valve for returning the pressure inside oil treatment tank 19 to atmospheric pressure.

[0089] Reference numeral 26 denotes a discharge pipe connected to the lower drain of the oil treatment tank 19, and 27 denotes a valve installed on the discharge pipe 26. Reference numeral 28 denotes a waste oil pipe that communicates with the discharge pipe 26 by switching the valve 29, and by switching the valve 29, the insulating oil 3E flowing through the discharge pipe 26 can be made to flow into the oil feed pipe 5d or into the waste oil pipe 28. Reference numeral 30 denotes a waste oil tank that stores the insulating oil 3E1 discharged through the waste oil pipe 28.

[0090] Next, we will explain the operation of the regeneration treatment device B. When regenerating insulating oil and performing maintenance and inspection on multiple oil-filled electrical devices, first, oil supply pipe 14a is inserted into tank 1A of the first oil-filled electrical device, and valve 34a is switched to connect the inside of tank 1A to the inside of oil storage tank 31A via oil supply pipes 14a and 32a.

[0091] In this state, vacuum pump 33a is driven to transfer insulating oil 3A from tank 1A to oil reservoir tank 31A through oil feed pipes 14a and 32a. Next, oil feed pipe 14a is moved into tank 1B of the second oil-filled electrical device, and maintenance and inspection of the first oil-filled electrical device is carried out. If any abnormalities such as malfunctions are discovered during the maintenance and inspection, repairs are carried out.

[0092] Once the maintenance and inspection (including repairs) of the first oil-filled electrical device is completed, valves 34a and 34b are switched to connect the inside of tank 1B of the second oil-filled electrical device to the inside of oil reservoir tank 31B via oil supply pipes 14a and 32b.

[0093] In this state, vacuum pump 33b is driven to transfer insulating oil 3B from tank 1B to oil reservoir tank 31B through oil feed pipes 14a and 32b. Next, oil feed pipe 14a is moved into tank 1C of the third oil-filled electrical device, and maintenance and inspection of the second oil-filled electrical device is carried out. If any abnormalities such as malfunctions are discovered during the maintenance and inspection, repairs are carried out.

[0094] At the same time, valves 18 and 36a are switched and one of valves 13c to 13e is opened, and pump 10 is driven while oil reservoir tank 31A and oil treatment tank 19 are in communication with each other, causing insulating oil 3A to flow into pipe 9 of filtration device 4a.

[0095] In the filtration device 4a, the dynamic pressure of the insulating oil 3A flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3A is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3A flows to the oil supply pipe 5j, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0096] When flowing to oil supply pipe 5j, the oil passes through valve 13e and then flows to oil supply pipe 35e. When flowing to filter 6b, solids such as carbon and sludge are removed by an adsorbent (e.g., white clay) in filter 6b, and then flows to oil supply pipe 35e via valve 13d. When flowing to filter 6a, solids such as carbon and sludge are removed by an adsorbent (e.g., activated alumina) in filter 6a, and then flows to oil supply pipe 35e via valve 13c.

[0097] When the insulating oil 3A is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3A to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3A is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3A with the heater 7.

[0098] The filters 6a and 6b that make up the filtration device 4a become clogged with the accumulation of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3A measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading on the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filters 6a and 6b.

[0099] The insulating oil 3A that has flowed into the oil feed pipe 35e is sprayed in the form of a shower or mist from the nozzles 20 of the oil treatment tank 19 into the oil treatment tank 19. Moisture and decomposition gases are removed from the insulating oil 3A that has been sprayed in the form of a shower or mist, and the oil is stored in the oil treatment tank 19.

[0100] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0101] When the pressure is reduced, the insulating oil 3A in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gas contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0102] After the degassing process, the insulating oil 3E is returned to the tank 1A through the discharge pipe 26 and the oil supply pipe 5k by opening the valves 25 and 27, connecting the discharge pipe 26 and the oil supply pipe 5d by the valve 29, and driving the pump 37.

[0103] The insulating oil 3A in the tank 1A is passed through the filtration device 4a and the oil treatment tank 19 to improve the degree of deterioration, and can be returned to the tank 1A as regenerated oil. By repeating this regeneration process, the measurement value by the measuring instrument 12 on the oil supply pipe 5k improves, and the regeneration of the insulating oil in the first tank 1A is completed.

[0104] Once the maintenance and inspection (including repairs) of the second oil-filled electrical device and the regeneration of the insulating oil of the first oil-filled electrical device are completed, valve 34b is switched to connect the inside of tank 1C of the third oil-filled electrical device to the inside of oil reservoir tank 31C via oil supply pipes 14a and 32c.

[0105] In this state, the vacuum pump 33c is driven to transfer the insulating oil 3C in the tank 1C to the oil reservoir tank 31C through the oil transfer pipes 14a and 32c. Once all the insulating oil 3C in the tank 1C has been transferred, maintenance and inspection of the third oil-filled electrical device is carried out. If any abnormalities such as breakdowns are discovered during the maintenance and inspection, repairs are carried out.

[0106] At the same time, valves 18 and 36b are switched and one of valves 13c to 13e is opened to connect oil reservoir tank 31B and oil treatment tank 19, and pump 10 is driven to flow insulating oil 3B into pipe 9 of filter device 4a.

[0107] In the filtration device 4a, the dynamic pressure of the insulating oil 3B flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3B is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3B flows to the oil supply pipe 5j, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0108] When flowing to oil supply pipe 5j, the oil passes through valve 13e and then flows to oil supply pipe 35e. When flowing to filter 6b, solids such as carbon and sludge are removed by an adsorbent (e.g., white clay) in filter 6b, and then flows to oil supply pipe 35e via valve 13d. When flowing to filter 6a, solids such as carbon and sludge are removed by an adsorbent (e.g., activated alumina) in filter 6a, and then flows to oil supply pipe 35e via valve 13c.

[0109] When the insulating oil 3B is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3B to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3B is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3B with the heater 7.

[0110] The filters 6a and 6b that make up the filtration device 4a become clogged with the accumulation of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3B measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading on the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filters 6a and 6b.

[0111] The insulating oil 3B flowing through the oil feed pipe 35e is sprayed in the form of a shower or mist from the nozzle 20 of the oil treatment tank 19 into the oil treatment tank 19. Moisture and decomposition gases are removed from the insulating oil 3B sprayed in the form of a shower or mist, and the oil is stored in the oil treatment tank 19.

[0112] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0113] When the pressure is reduced, the insulating oil 3E in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0114] After the degassing process, the insulating oil 3E is returned to the tank 1B from the discharge pipe 26 through the oil supply pipe 5k by opening the valves 25 and 27, connecting the discharge pipe 26 to the oil supply pipe 5k using the valve 29, and driving the pump 37.

[0115] The insulating oil 3B in the tank 1B is passed through the filtration device 4a and the oil treatment tank 19 to improve the degree of deterioration, and can be returned to the tank 1B as regenerated oil. By repeating this regeneration process, the measurement value by the measuring instrument 12 on the oil supply pipe 5k improves, and the regeneration of the insulating oil in the second tank 1B is completed.

[0116] Once the maintenance and inspection (including repairs) of the third oil-filled electrical device and the regeneration of the insulating oil of the second oil-filled electrical device are completed, valve 36b is switched and one of valves 13c to 13e is opened, and pump 10 is driven while oil reservoir tank 31C is connected to oil treatment tank 19, and insulating oil 3C is caused to flow into piping 9 of filtration device 4a.

[0117] In the filtering device 4a, the dynamic pressure of the insulating oil 3C flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3C is heated to a predetermined temperature (40°C) by a heater 7. The temperature of the insulating oil 3C is measured by a measuring device such as a temperature sensor (not shown). The heated insulating oil 3C flows to the oil supply pipe 5j, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0118] When flowing to oil supply pipe 5j, the oil passes through valve 13e and then flows to oil supply pipe 35e. When flowing to filter 6b, solids such as carbon and sludge are removed by an adsorbent (e.g., white clay) in filter 6b, and then flows to oil supply pipe 35e via valve 13d. When flowing to filter 6a, solids such as carbon and sludge are removed by an adsorbent (e.g., activated alumina) in filter 6a, and then flows to oil supply pipe 35e via valve 13c.

[0119] When the insulating oil 3C is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3C to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3C is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3C with the heater 7.

[0120] The filters 6a and 6b that make up the filtration device 4a become clogged with the accumulation of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3C measured by the pressure gauge 8 on the pipe 9 rises, and the reading on the pressure gauge 8 makes it possible to determine when it is time to replace the filters 6a and 6b. It is also possible to configure the system to be easier for the manager to manage, for example by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filters 6a and 6b.

[0121] The insulating oil 3C flowing through the oil feed pipe 35e is sprayed in the form of a shower or mist from the nozzle 20 of the oil treatment tank 19 into the oil treatment tank 19. Moisture and decomposition gases are removed from the insulating oil 3C sprayed in the form of a shower or mist, and the oil is stored in the oil treatment tank 19.

[0122] Next, the valve 18 is closed and the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0123] When the pressure is reduced, the insulating oil 3E in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3E in the oil treatment tank 19 can be further removed.

[0124] After the degassing process, the insulating oil 3E is returned to the tank 1C from the discharge pipe 26 through the oil supply pipe 5k by opening the valves 25 and 27, connecting the discharge pipe 26 to the oil supply pipe 5k using the valve 29, and driving the pump 37.

[0125] The insulating oil 3C in the tank 1C is passed through the filtration device 4a and the oil treatment tank 19 to improve the degree of deterioration, and can be returned to the tank 1C as regenerated oil. By repeating this regeneration process, the measurement value by the measuring instrument 12 on the oil supply pipe 5k improves, and the regeneration of the insulating oil in the third tank 1C is completed.

[0126] 1 can also mix new oil 3D and return it to tanks 1A-1C during the process of regenerating insulating oil 3A-3C in tanks 1A-1C. In this case, valve 17 on oil supply pipe 16 is opened around the time of oil transfer from oil reservoir tanks 31A-31C to oil treatment tank 19, and vacuum pump 21 transfers new oil 3D from oil supply pipe 16 through oil transfer pipe 14b and nozzle 20 into oil treatment tank 19. In oil treatment tank 19, insulating oil 3A-3C transferred from one of oil reservoir tanks 31A-31C and new oil 3D in new oil tank 15 are mixed together.

[0127] The process of returning the mixed insulating oil 3E to the tanks 1A to 1C via the oil supply pipe 5k by the pump 37 is the same as that described above, and therefore will not be described here. The insulating oil 3E, which is a mixture of the insulating oils 3A to 3C and the new oil 3D, has a dramatically improved degree of deterioration, and the measurement value measured by the measuring instrument 12 also improves.

[0128] If the insulating oil 3A-3C in the tanks 1A-1C has deteriorated so much that it cannot be regenerated by the regeneration process described above, the insulating oil 3A-3C in the tanks 1A-1C can be discarded and only new oil 3D can be poured into the tanks 1A-1C. When pouring only new oil 3D into the tanks 1A-1C, first, one of the oil reservoir tanks 31A-31C is connected to the inside of the oil treatment tank 19 by switching the valve 18.

[0129] In this state, by driving the pump 10, the insulating oil 3A to 3C in one of the oil reservoir tanks 31A, 31B, 31C is sucked up through the oil supply pipe 35d, and the insulating oil 3A to 3C is transferred through the filter device 4a, the oil supply pipes 35e, 14b, and the nozzle 20 into the oil treatment tank 19.

[0130] The insulating oil 3E accumulated in the oil treatment tank 19 is discharged from the discharge pipe 26 through the waste oil pipe 28 to the waste oil tank 30 by opening the valves 25 and 27 and switching the valve 29 to connect the discharge pipe 26 and the waste oil pipe 28.

[0131] Next, with valves 25 and 27 closed and valve 17 open, pump 21 is driven to transfer new oil 3D from new oil tank 15 into oil treatment tank 19. Once new oil 3D has accumulated in oil treatment tank 19, valve 18 is switched to release the communication between oil supply pipe 16 and oil transfer pipe 14b. Then, valve 29 is switched to connect discharge pipe 26 and oil supply pipe 5k, and pump 37 is driven to supply new oil 3D from oil treatment tank 19 through oil supply pipe 5k to one of tanks 1A to 1C.

[0132] The operation of the regeneration treatment device B can be automatic or semi-automatic. For example, if the measurement by the measuring device 12 shows that the insulating oil is not very deteriorated, the various valves and pumps are controlled so that filtration by the filter 6a (6b) is not performed and only degassing treatment is performed in the oil treatment tank 19.

[0133] If the insulating oil is severely deteriorated, the various valves and pumps are controlled to perform both the selection and filtration by the filter 6a (6b) and the degassing treatment in the oil treatment tank 19. Alternatively, the deterioration state of the insulating oil 3A to 3C in the tanks 1A to 1C may be resolved by controlling the various valves and pumps to mix the insulating oil 3A to 3C in the tanks 1A to 1C with the insulating oil 3D in the new oil tank 15 and return the mixture to the tanks 1A to 1C.

[0134] If the insulating oil is severely deteriorated and cannot be regenerated, the various valves and pumps are controlled to discharge the insulating oil 3A to 3C into the waste oil tank 30 and to pour only new oil 3D into the tanks 1A to 1C. Naturally, all or part of the control of the various valves and pumps may be manually operated.

[0135] 2 illustrates a case where oil inflow prevention unit 24 is attached to oil treatment tank 19, but the vacuum pump 21 and valve 22 may be attached at the positions shown by dotted lines in Fig. 2, and insulating oil 3E may be prevented from flowing into vacuum pump 21 by drawing a vacuum from the top of oil treatment tank 19. With this configuration, oil inflow prevention unit 24 is not necessary.

[0136] Furthermore, the regeneration treatment device B is configured to be able to select and filter the filters 6a and 6b containing the optimal adsorbent according to the measurement value from the measuring device 12. While Fig. 2 illustrates the case where two filters 6a and 6b are provided, the number of filters constituting the present invention is not limited to two, and the regeneration treatment device B may be configured with more than two filters. By installing additional valves downstream of the valve 11a according to the number of filters, it is possible to accommodate a large number of filter selections.

[0137] In the above embodiment, the deterioration degree of the insulating oil is measured by the measuring instrument 12, but the deterioration state may be determined from the color of the insulating oil sampled from the tanks 1A to 1C of the oil-filled electrical equipment. In this case, the control of various valves and pumps according to the deterioration degree of the insulating oil is semi-automated.

[0138] Furthermore, the order of operation of the various valves and pumps is not limited to the order described above, and it goes without saying that the order of operation may be changed as long as the contents of the present invention can be realized. Furthermore, although the various valves are shown with a single symbol in Figures 1 and 2, they do not have to be single valves, and the various valves may be configured by combining multiple valves so as to realize the above functions.

[0139] 1 and 2, insulating oil 3A, 3B, 3C is transferred to oil reservoir tanks 31A, 31B, 31C via oil supply pipes 14a, 32a, 32b, 32c and valve 34a, and then sent to filtration device 4a via valves 36a, 36b and oil supply pipes 35a, 35b, 35c, 35d, but it is also possible to provide only valves 34a, 36a, oil supply pipes 32a, 35a, and pump 33a, and to selectively select oil reservoir tanks 31A, 31B, 31C by appropriately changing the positions of oil supply pipes 32a, 35a. This configuration makes it possible to reduce the number of oil supply pipes and valves, thereby reducing the cost of the device.

[0140] Furthermore, the deterioration state of the insulating oil is not limited to the values ​​measured by the conductivity meter or dielectric meter described above, but may also be measured based on one or more physical property values ​​of the insulating oil, such as kinematic viscosity, density, turbidity, transmittance, volume resistivity, dielectric loss tangent, surface tension, acid value, breakdown voltage, moisture content, and flash point.

[0141] As described above, the insulating oil regeneration treatment device of the present invention can efficiently perform maintenance and inspection (including repair) of multiple oil-filled electrical devices and regenerate insulating oil in a short time.

[0142] In addition, depending on the deterioration state of the insulating oil, it is possible to select between regeneration and disposal. Furthermore, depending on the deterioration state of the insulating oil, it is possible to select the regeneration method. [Industrial Applicability]

[0143] It can be applied to the regeneration / disposal of insulating oil from multiple oil-filled electrical devices. [Explanation of symbols]

[0144] 1A, 1B, 1C tanks 2A, 2B, 2C Electrical equipment body 2A1, 2B1, 2C1 coils 2A2, 2B2, 2C2 iron core 3A, 3B, 3C Insulating oil 3D insulating oil (new oil) 3E insulating oil (before and after degassing) 3E1 Insulating oil (waste oil) 4a Filtration device 5c, 5e, 5f, 5g, 5k oil supply piping 5d, 5h, 5i, 5j, 14a, 14b, 32a, 32b, 32c, 35a, 35b, 35c, 35d, 35e Oil pipe 6a, 6b filters 7 Heater 8, 23 Pressure gauge 9 Piping 10, 33a, 33b, 33c, 37 Pump 11a, 13c, 13d, 13e, 17, 18, 22, 25, 26, 29, 34a, 34b, 36a, 36b valves 12 Measuring instruments (conductivity meters, dielectric meters, etc.) 15 New oil tank 16 Oil supply pipe 19 Oil treatment tank 20 nozzles 21 Vacuum pump 24 Oil inflow prevention part 26 Discharge piping 28 Waste oil piping 30 Waste oil tank 31A, 31B, 31C Oil Sump Tank A, B Insulating oil regeneration treatment equipment

Claims

1. An insulating oil regeneration method in which a plurality of oil-filled electrical equipment perform the following steps in parallel in the order given: a first step of transferring insulating oil from oil-filled electrical equipment and storing it in an oil tank; a second step of maintaining and inspecting the oil-filled electrical equipment to which the insulating oil has been transferred; and a third step of transferring the insulating oil in the oil tank, regenerating it, and then returning the insulating oil to the oil-filled electrical equipment, wherein the second oil-filled electrical equipment performs the first and second steps while the previous oil-filled electrical equipment is performing the third step.

2. 2. The insulating oil regeneration method according to claim 1, wherein the insulating oil regeneration step is selectable between a step of regenerating the insulating oil and a step of discarding the insulating oil.

3. 3. The method for regenerating insulating oil according to claim 2, wherein the step of regenerating the insulating oil comprises at least one of a step of degassing the insulating oil and a step of filtering the insulating oil.

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